Deck 8: Microbial Metabolism: The Chemical Crossroads of Life

Question 1

The term used to describe all of the chemical reactions within a cell is ______.

A) catabolism
B) redox reactions
C) phosphorylation
D) metabolism
E) cellular respiration

Answer 1

D

Question 2

An apoenzyme is ______.

A) part of a simple enzyme
B) also called a coenzyme
C) the protein part of a holoenzyme
D) often an inorganic metal ion
E) an RNA molecule

Answer 2

C

Question 3

Reactants are converted to products by

A) enzymes releasing energy.
B) breaking and forming bonds.
C) enzymes binding to products.
D) reactants always releasing energy.

Answer 3

B

Question 4

Enzymes that catalyze the removal of a a functional group and its subsequent attachment to a new substrate are called ______.

A) transferases
B) oxidoreductases
C) isomerases
D) lyases
E) ligases

Question 5

The cell's metabolic reactions involve the participation of ______ that lower the activation energy needed for the initiation of a reaction.

A) cofactors
B) vitamins
C) enzymes
D) ATP
E) coenzymes

Question 6

All of the following are exoenzymes except ______.

A) ATP synthase
B) streptokinase
C) penicillinase
D) collagenase

Question 7

The bacterial genus Bacillus can utilize starch as a nutrient by splitting the starch molecule into smaller molecules of glucose with the addition of water.The enzymes to do this would be classified as ______.

A) transferases
B) oxidoreductases
C) ligases . hydrolases
E) isomerases

Question 8

Anabolic reactions that involve ligases and release water molecules when bonds are formed are called ______ reactions.

A) reduction
B) condensation
C) oxidation
D) transfer

Question 9

A holoenzyme is a combination of a protein and one or more substances called ______.

A) substrates
B) apoenzymes
C) catalysts
D) cofactors
E) ribozymes

Question 10

The formation of peptide bonds between amino acids to build a polypeptide is an example of ______.

A) anabolism
B) phosphorylation
C) fermentation
D) catabolism
E) glycolysis

Question 11

Enzymes are

A) broken down in reactions that require energy input.
B) proteins that function as catalysts.
C) used up in chemical reactions.
D) not needed for catabolic reactions.
E) carbohydrate or protein in composition.

Question 12

Each of the following are true of enzymes except

A) they can be used over and over.
B) they may or may not require cofactors.
C) their active site is specific to the substrate.
D) they increase the activation energy of a reaction.
E) their action may involve minerals.

Question 13

Ribozymes are ______.

A) ribosomes which catalyze reactions
B) unique to prokaryotes
C) unique to eukaryotes
D) catalysts for RNA splicing
E) catalysts for DNA splicing

Question 14

The most likely place where an exoenzyme participates in a chemical reaction is ______.

A) in mitochondria
B) within the cell membrane
C) in lysosomes
D) in cytoplasm
E) outside of the cell

Question 15

Important components of coenzymes are _______.

A) vitamins
B) metallic ions
C) active sites
D) substrates
E) ribozymes

Question 16

During aerobic cellular respiration,the final electron acceptor is ______.

A) pyruvic acid
B) oxygen
C) nitrate
D) cytochrome C
E) FAD

Question 17

Enzymes that are only produced when substrate is present are termed ______.

A) exoenzymes
B) endoenzymes
C) constitutive enzymes
D) induced enzymes
E) conjugated enzymes

Question 18

Enzymes that catalyze the removal of electrons from one substrate and the addition of electrons to another are called ______.

A) transferases
B) oxidoreductases
C) lyases
D) isomerases
E) ligases

Question 19

Your bacterium is growing on a type of medium called casein agar,which contains milk protein (casein).There is a clear zone around the growth area of the bacterium,showing that it is synthesizing the enzymes needed to catalyze the breakdown of casein.These enzymes are considered ______.

A) apoenzymes
B) exoenzymes
C) ribozymes
D) endoenzymes

Question 20

A type of cofactor would be ______.

A) vitamins
B) metallic ions
C) active sites
D) substrates
E) ribozymes

Question 21

Noncompetitive inhibition is best described as

A) the substrate binding to DNA, blocking enzyme transcription.
B) the end product binding to DNA, blocking enzyme transcription.
C) the substrate binding to enzyme in a regulatory site.
D) the end product binding to enzyme in noncompetitive site.

Question 22

Which of the following is not a process that regenerates ATP?

A) Oxidative phosphorylation
B) Reductive phosphorylation
C) Substrate-level phosphorylation
D) Photophosphorylation

Question 23

Each of the following are electron carriers except ______.

A) NAD
B) FAD
C) NADP
D) FADP

Question 24

The step involving ATP,hexokinase,and the phosphorylation of glucose to glucose-6-phosphate is

A) the final step of the Krebs cycle.
B) the first redox reaction of the electron transport system.
C) an example of oxidative phosphorylation.
D) an example of substrate-level phosphorylation.
E) an example of photophosphorylation.

Question 25

In the cell,energy released by electrons is often used to phosphorylate ______.

A) ATP
B) ADP
C) pyruvic acid
D) oxygen
E) NAD

Question 26

FAD,NADP,NAD,and coenzyme A are all carriers of ________.

A) hydrogens
B) electrons
C) ATP
D) Both hydrogens and electrons are correct.

Question 27

Exergonic reactions

A) include synthesis of large carbohydrates.
B) only occur in heterotrophs.
C) occur during aerobic cellular respiration.
D) do not occur in anaerobic cellular respiration.
E) occur when ADP binds to inorganic phosphate to form ATP.

Question 28

Enzymes that function inside a cell are ______.

A) apoenzymes
B) exoenzymes
C) constitutive enzymes
D) regulated enzymes
E) endoenzymes

Question 29

Each of the following are denaturing agents except ______.

A) high temperature
B) low temperature
C) high pH
D) low pH

Question 30

Which of the following is not part of the step that occurs between glycolysis and the Krebs cycle?

A) Reduction of NAD+
B) Coenzyme A attaches to an acetyl group
C) Oxidation of pyruvic acid
D) Pyruvic acid accepts electrons from NADH

Question 31

Metabolic pathways that regenerate their starting molecule are called _____ pathways.

A) linear
B) bidirectional
C) convergent
D) cyclic
E) divergent

Question 32

In addition to electrons,which of the following is also involved in electron transfer?

A) ADP
B) Glucose
C) Carbon
D) Hydrogen
E) Carbon dioxide

Question 33

When the product of reaction A becomes the reactant of reaction B,this exemplifies a _______ metabolic pathway.

A) linear
B) bidirectional
C) convergent
D) cyclic
E) divergent

Question 34

The formation of citric acid from oxaloacetic acid and an acetyl group begins ______.

A) glycolysis
B) the electron transport system
C) the Krebs cycle
D) fermentation
E) oxidative phosphorylation

Question 35

Substrate-level phosphorylation occurs in

A) glycolysis and the electron transport chain.
B) photosynthesis and glycolysis.
C) glycolysis and the Krebs cycle.
D) the Krebs cycle and the electron transport system.
E) the electron transport system only.

Question 36

Most electron carriers are ______.

A) coenzymes
B) enzymes
C) hydrogen
D) inorganic phosphate

Question 37

Glycolysis uses 2 ATP and produces

A) 2 ATP only if oxygen is present.
B) 2 ATP without oxygen.
C) 4 ATP only if oxygen is present.
D) 4 ATP without oxygen.

Question 38

Enzymes that are always present,regardless of the amount of substrate,are ______.

A) apoenzymes
B) exoenzymes
C) constitutive enzymes
D) regulated enzymes
E) endoenzymes

Question 39

All of the following pertain to glycolysis except

A) it occurs without oxygen.
B) it ends with formation of pyruvic acid.
C) it occurs during fermentation.
D) it degrades glucose to CO₂ and H₂O.
E) it involves reduction of NAD.

Question 40

When enzyme action stops due to a buildup of end product that acts as a regulatory molecule,this control is called ______.

A) competitive inhibition
B) enzyme induction
C) enzyme repression
D) noncompetitive inhibition

Question 41

In which stage of aerobic respiration is water produced?

A) Glycolysis
B) The Krebs cycle
C) The electron transport system

Question 42

In which pathway is the most NADH generated?

A) The electron transport system
B) The Krebs cycle
C) Glycolysis
D) Alcoholic fermentation
E) Mixed acid fermentation

Question 43

As the electron transport carriers shuttle electrons,they actively pump _____ into the outer membrane compartment,setting up a concentration gradient called the proton motive force.

A) ATP
B) phosphate
C) hydrogen ions
D) oxygen
E) NADH

Question 44

Fermentation ______.

A) requires an organic electron acceptor
B) requires oxygen
C) only occurs in aerobic organisms
D) is equivalent to aerobic respiration in ATP production
E) is the same as anaerobic respiration

Question 45

What chemical causes death in many eukaryotes because it blocks cytochrome C oxidase?

A) Copper
B) Iron
C) Cyanide
D) Oxygen
E) Carbon monoxide

Question 46

Each NADH that enters the electron transport system results in the production of _____ ATPs.

A) 2
B) 3
C) 24
D) 36
E) 38

Question 47

The reactions of fermentation function to produce _______ molecules for further use in glycolysis.

A) pyruvic acid
B) ATP
C) NAD+
D) NADH
E) glucose

Question 48

During which phase of cellular respiration is the majority of ATP formed?

A) Electron transport system
B) The Krebs cycle
C) Glycolysis
D) Processing of pyruvic acid for the Krebs cycle
E) All phases produce the same number of ATP molecules.

Question 49

When glucose is broken down by glycolysis during bacterial fermentation,what is the usual net production of ATP?

A) 2
B) 3
C) 24
D) 36
E) 38

Question 50

How many carbon dioxide molecules are produced by the complete aerobic breakdown of one glucose molecule?

A) 2
B) 3
C) 4
D) 5
E) 6

Question 51

Which of the following is not a photosynthetic pigment?

A) Carotenoid
B) Leukophyll
C) Phycobilin
D) Chlorophyll

Question 52

In bacterial cells,the electron transport system is located in the ______.

A) cell membrane
B) mitochondria
C) chloroplasts
D) ribosomes
E) cytoplasm

Question 53

Which of the following is not true of anaerobic respiration?

A) It involves glycolysis.
B) It generates some ATP.
C) It utilizes an electron transport system.
D) It uses the same final electron acceptor as aerobic respiration.

Question 54

The redox carriers of the electron transport system that have a tightly bound metal atom responsible for accepting and donating electrons are ______.

A) NAD molecules
B) FAD molecules
C) NADP molecules
D) the cytochromes
E) the flavoproteins

Question 55

In bacterial cells,when glucose is completely oxidized by all the pathways of aerobic cellular respiration,what is the maximum number of ATP generated?

A) 2
B) 3
C) 24
D) 36
E) 38

Question 56

An oxidase detection test can be used to identify certain bacteria because they are missing or lack expression of ______.

A) cytochrome C oxidase
B) NAD
C) mitochondria
D) ATP synthase
E) coenzyme Q

Question 57

Each FADH₂ from the Krebs cycle that enters the electron transport system results in the production of _____ ATP(s).

A) 1
B) 2
C) 3
D) 4
E) 5

Question 58

The majority of NADH is produced in ______.

A) glycolysis
B) the Krebs cycle
C) the electron transport system
D) photosynthesis
E) fermentation

Question 59

Mixed acid fermentation

A) produces butyric acid.
B) occurs in all bacteria.
C) produces several different acids plus CO₂ and H₂ gases.
D) is seen in Streptococcus and Lactobacillus.
E) also produces ethanol.

Question 60

Reduction of nitrogen-oxygen ions and compounds by some bacteria is called ______.

A) aerobic respiration
B) denitrification
C) nitrification
D) fermentation
E) deamination

Question 61

The principle sites of amphibolic interaction occur during ______.

A) glycolysis and photosynthesis
B) the Krebs cycle and the electron transport system
C) glycolysis and the Krebs cycle
D) fermentation and the Krebs cycle
E) fermentation and glycolysis

Question 62

Building block molecules for biosynthetic pathways come from the cell's catabolic pathways and from the environment.

Question 63

Denaturing an apoenzyme will destroy the three-dimensional shape of the protein,making it nonfunctional.

Question 64

Which of the following is not true of the light-dependent reactions of photosynthesis?

A) They occur in thylakoid membranes.
B) They generate NADPH.
C) They generate glucose from CO₂ and H₂O.
D) The photons cause magnesium to release electrons.
E) ATP is generated by a chemiosmotic mechanism.

Question 65

All aerobic bacterial species have identical electron acceptors in their electron transport systems.

Question 66

Intermediates from the Krebs cycle can be converted to amino acids by the process of ______.

A) amination
B) deamination
C) phosphorylation
D) beta oxidation
E) gluconeogenesis

Question 67

The process of forming glucose from various metabolic intermediates is called ______.

A) glycolysis
B) amphibolism
C) phosphorylation
D) amination
E) gluconeogenesis

Question 68

Glyceraldehyde-3-phosphate is an intermediary of glycolysis that can also be utilized in biosynthetic pathways.

Question 69

Exoenzymes from pathogens are called virulence factors.

Question 70

Hydrolysis reactions are catabolic reactions that use water to split the reactant into smaller subunits.

Question 71

The unknown bacterium that you are testing makes the enzyme phenyalanine deaminase,as indicated by the results of a phenylalanine test.This enzyme facilitates the removal of a/an ______ group from the organic compound so it can be converted into an intermediate compound for the Krebs cycle.

A) carboxyl
B) amino
C) phosphate
D) hydroxyl

Question 72

ATP synthase is a complex enzyme needed for oxidative phosphorylation.

Question 73

Oxygen-containing ions are used by some bacteria in their electron transport system.

Question 74

Microbes can utilize only carbohydrates for energy production.

Question 75

ATP molecules are catalysts that lower the activation energy needed to initiate a reaction.

Question 76

The property of organisms to integrate catabolic and anabolic pathways to improve cell efficiency is called ______.

A) metabolism
B) amphibolism
C) anabolism
D) catabolism
E) biosynthesis

Question 77

Only yeast produce alcohol as a fermentation product.

Question 78

ATP is composed of deoxyribose,adenine,and three phosphate groups.

Question 79

The best way to control a metabolic pathway is to control the fastest enzyme in the series.

Question 80

Which of the following characterize the Calvin cycle?

A) A process that requires light
B) Nitrogen is fixed into an organic form
C) Produces glucose as an end product
D) Produces carbon dioxide and water
E) Produces oxygen